RESUMO
Aging processes have become an attractive field for researchers and annual fish have been used as biological models. However, the study on the changes in age-associated markers during the normal aging in wild populations of annual fish remains open. Austrolebias is a genus of Neotropical annual killifishes, distributed mainly in ephemeral pools across grassland floodplains of temperate South America and represent an emerging biological model for aging research, but studies investigating rapid aging and senescence in this genus of annual fish are almost non-existent. This study was undertaken to examine the changes in age-associated liver markers at the different developmental stages in wild populations of Austrolebias minuano. We demonstrate that A. minuano has a number of liver alterations of different severities throughout the life cycle, suggesting that these changes tend to increase with age. Our results revealed that > 70% of the analyzed livers presented alterations. Thus, our study should instigate new approaches on aging using Neotropical annual fish, and could be useful to improve the knowledge already provided by consecrated biological aging models as e.g. Nothobranchius killifishes.
Assuntos
Envelhecimento/fisiologia , Fígado Gorduroso/metabolismo , Peixes Listrados/fisiologia , Lipofuscina/análise , Fígado/metabolismo , Animais , Biomarcadores/metabolismo , Fundulidae , Modelos Biológicos , beta-Galactosidase/análiseRESUMO
Currently there is a growing concern, in both population and governments, to identify the effects of substances commonly disposed of into rivers and lakes, on aquatic fauna and flora. Thus the objective of the present study was to verify effects of biodegradable detergents and water from an urban lake on gills and liver of two neotropical fish species of great economic importance, Astyanax altiparanae and Prochilodus lineatus. In order to do so, lipofuscin, also called the ageing pigment, was used as bioindicator. After one and five months of experiment both tissues accumulated this pigment. These data are discussed from physiological points of view, related with lipid peroxidation and mitochondrial damage.
Existe una preocupación creciente de la población y los gobiernos para identificar los efectos de substancias comúnmente arrojadas en ríos y lagos, sobre la fauna y flora acuática. El objetivo fue verificar los efectos de detergentes biodegradables y agua de un lago urbano sobre las branquias e hígado de dos especies de peces neo-tropicales de gran importancia económica, Astyanax altiparanae y Prochilodus lineatus. Analizamos los pigmentos de lipofuscina, también llamado pigmento de envejecimiento, el que fue utilizado como biomarcador. Después de uno y cinco meses de experimento, ambos tejidos acumulados con el pigmento fueron analizados. Los datos fueron discutidos desde el punto de vista fisiológico, relacionado con la peroxidación lipídica y daño mitocondrial.
Assuntos
Animais , Poluentes Químicos da Água/toxicidade , Detergentes/toxicidade , Peixes , Brânquias/efeitos dos fármacos , Fígado/efeitos dos fármacos , Biomarcadores/análise , Brânquias/patologia , Lipofuscina/análise , Fígado/patologiaRESUMO
Aging of long-lived post-mitotic cells is characterized as a progressive and irreversible reduction of functional activity. In such cells, mitochondria are organelles critical for bioenergetic supply, whose turnover is mediated by an autophagic-lysosomal pathway. In human teeth, odontoblasts are post-mitotic cells responsible for sensory function and dentin preservation. Here, human odontoblasts were processed for immunohistochemistry with antibodies against mitochondrial (MTCO2) and lysosomal (LAMP2) markers, and comparatively analyzed in two age groups (young-adult and adult) with light and electron microscopy. Selective engulfment of mitochondrial profiles into autophagic vacuoles is common in young-adult odontoblasts, suggesting a microautophagic pathway. With age, the odontoblast layer is reduced in width, and mitochondrial elements converge around large clusters of autofluorescent lipofuscin deposits. Age-related changes in odontoblasts are observed as a long-term process in which the progressive accumulation of intralysosomal debris limits the autophagic turnover of mitochondrial components, causing an eventual decline in physiological cell functions, which leads to increased vulnerability under stress conditions.
Assuntos
Autofagia/fisiologia , Senescência Celular/fisiologia , Lipofuscina/metabolismo , Mitocôndrias/fisiologia , Odontoblastos/citologia , Adolescente , Adulto , Idoso , Humanos , Lipofuscina/análise , Lisossomos/fisiologia , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Odontoblastos/metabolismo , Vacúolos/fisiologia , Adulto JovemRESUMO
Poisoning by Indigofera lespedezioides is reported in horses in the state of Roraima, northern Brazil. The main clinical signs are anorexia, sleepiness, unsteady gait, severe ataxia, weakness, stumbling, and progressive weight loss. To induce the disease experimentally, a 7-year-old horse was introduced in a small paddock invaded by the plant. The first nervous signs were observed 44 days from the start of grazing. The animal was euthanized on day 59. No significant gross lesions were observed upon necropsies of the experimental horse as well as one spontaneously affected horse. Upon histologic examination neuronal lipofuscinosis was observed in the brain, cerebellum, and spinal cord. Wallerian-type degeneration was observed on some mesencephalic tracts. Neuronal and axonal degeneration and lipofuscinosis were observed on electron microscopy examination. Indospicine was detected in four samples of I. lespedezioides with concentrations ranging from 63 to 1178 µg/g whereas nitro toxins could be detected in only one of the samples at a concentration of 2.5 mg/g. In conclusion, poisoning by I. lespedezioides is very similar to those poisonings by Indigofera linnaei and Indigofera hendecaphylla. Based on the preponderance of indospince and lack of nitro toxins in the samples it is proposed that indospicine is the toxic compound responsible for the poisoning.
Assuntos
Doenças dos Cavalos/etiologia , Indigofera/intoxicação , Intoxicação por Plantas/veterinária , Criação de Animais Domésticos , Animais , Ataxia/etiologia , Ataxia/fisiopatologia , Ataxia/veterinária , Brasil , Cerebelo/química , Cerebelo/ultraestrutura , Feminino , Doenças dos Cavalos/metabolismo , Doenças dos Cavalos/patologia , Doenças dos Cavalos/fisiopatologia , Cavalos , Indigofera/química , Lipofuscina/análise , Masculino , Mesencéfalo/química , Mesencéfalo/ultraestrutura , Neurônios/química , Neurônios/ultraestrutura , Norleucina/análogos & derivados , Norleucina/análise , Norleucina/toxicidade , Intoxicação por Plantas/metabolismo , Intoxicação por Plantas/patologia , Intoxicação por Plantas/fisiopatologia , Índice de Gravidade de Doença , Medula Espinal/química , Medula Espinal/ultraestrutura , Fatores de Tempo , Toxinas Biológicas/análise , Toxinas Biológicas/toxicidade , Degeneração Walleriana/veterináriaRESUMO
Odontoblasts are long-lived post-mitotic cells in the dental pulp, whose function is to form and maintain dentin. The survival mechanisms that preserve the viability of terminally differentiated odontoblasts during the life of a healthy tooth have not been described. In the present study, we characterized the autophagic-lysosomal system of human odontoblasts with transmission electron microscopy and immunocytochemistry, to analyze the mechanisms that maintain the functional viability of these dentinogenic cells. Odontoblasts were found to develop an autophagic-lysosomal system organized mainly by large autophagic vacuoles that are acid-phosphatase-positive to various degrees. These vacuoles expressed the autophagosomal and lysosomal markers LC3 and LAMP2, respectively, in an age-related pattern indicating the organization of a dynamic autophagic machinery. Progressive accumulation of lipofuscin within lysosomes indicates reduced lysosomal activity as a function of odontoblast aging. Our results suggest that autophagic activity in odontoblasts is a fundamental mechanism to ensure turnover and degradation of subcellular components. A reduction in the efficacy of this system might compromise cell viability and dentinogenic secretory capacity. In adult teeth, this condition is described as an 'old odontoblast' stage.
Assuntos
Autofagia/fisiologia , Senescência Celular/fisiologia , Polpa Dentária/citologia , Odontoblastos/fisiologia , Fosfatase Ácida/análise , Adolescente , Adulto , Idoso , Tamanho Celular , Sobrevivência Celular/fisiologia , Criança , Espaço Extracelular , Humanos , Imuno-Histoquímica , Membranas Intracelulares/ultraestrutura , Lipofuscina/análise , Proteína 2 de Membrana Associada ao Lisossomo , Proteínas de Membrana Lisossomal/análise , Lisossomos/ultraestrutura , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/análise , Pessoa de Meia-Idade , Odontoblastos/citologia , Vacúolos/ultraestrutura , Adulto JovemRESUMO
A preliminary study was done on the age-pigment lipofuscin content in the brains of captive Farfantepenaeus paulensis juveniles (5 months old) and wild adults (estimated age of 12-15 months). Random samples of 6 individuals were obtained from each group (juvenile and adult) for histological analysis. Serial sections (6 microns) of the brains were mounted without staining and observed in an epifluorescent microscope. The fluorescent images of the five most central sections of the olfactory lobe cell mass (OLCM) of each individual were digitized for image analysis. The lipofuscin granule mean diameter was similar in both groups (p > 0.05), however the lipofuscin area fraction (percentage of the OLCM occupied by pigment granules) was significantly higher (p < 0.05) in the adult shrimp. The detection of lipofuscin granules in 5 month old F. paulensis indicates that lipofuscin deposition probably takes place even earlier in the juvenile phase. Our results suggested that the amount of granules in the F. paulensis OLCM is related to age, but further studies are necessary to evaluate the relationship between lipofuscin content and the age of captive F. paulensis.
Assuntos
Química Encefálica , Decápodes/crescimento & desenvolvimento , Lipofuscina/análise , Fatores Etários , Animais , Decápodes/química , Microscopia de Fluorescência , Condutos Olfatórios/químicaRESUMO
Objetivo - Comparar o tamanho das células musculares e a presença de lipofuscina no coração de adultos necropsiados, subnutridos e controles. Método - De uma casuística inicial de 315 necropsias de adultos, foram excluídos casos com sinais de retenção hídrica, cardiopatias, hepatopatias, hipertensão e nefropatias. Subnutrição foi caracterizada pelo índice de massa corporal (IMC) <17kh/m2. Fragmentos de miocárdio foram processados para morfometria computadorizada, determinando-se a espessura dos miocardiócitos e a presença de lipofuscina. Resultados - Subnutridos (n=8) e controles (n=4) foram estatisticamente diferentes, respectivamente, quanto ao IMC (14,86+1,13 vs 22,02+0,9 kg/m2), relação peso cardíaco/peso corporal (0,68+0,09 vs 0,54+0,07 por cento), espessura de miocardiócitos (10,91+0,77 vs 12,90+54,4 por cento). Conclusão - Comparados aos controles, adultos subnutridos têm menores espessuras de miocardiócitos e presença de lipofuscina, fenômenos que refletir um distúrbio metabólico com repercussões clínicas danosas em pacientes terminais.
Assuntos
Adulto , Humanos , Feminino , Lipofuscina/análise , Miocárdio/patologia , Desnutrição Proteico-Calórica/patologia , Índice de Massa Corporal , Estudos de Casos e Controles , Estado Nutricional , Desnutrição Proteico-Calórica/complicaçõesRESUMO
PURPOSE: To compare cardiac muscle cells width and cardiomyocyte lipofuscin pigment presence between malnourished and non-malnourished necropsied adults. METHODS: Out of 315 necropsy protocols of adults randomly chosen, those with edema, ascitis, systemic arterial hypertension, chronic liver disease, and heart disease were excluded. Malnutrition was defined by body mass index (BMI) < 17 kg/m2. Cardiomyocytes morphometry study and lipofuscin pigment counts were performed. RESULTS: Malnourished (n = 8) and controls (n = 4), respectively, showed statistical differences in relation to BMI (14.86 +/- 1.13 vs 22.02 +/- 0.9 kg/m2), heart weight/body weight ratio (0.68 +/- 0.09 vs 0.54 +/- 0.07%), cardiomyocytes width (10.91 +/- 0.77 vs 12.90 +/- 1.82 microns) and lipofuscin pigment presence (39.1 vs 54.4%). CONCLUSION: When compared with controls, necropsied malnourished adults showed decreased myocardial fibers diameters and lower lipofuscin pigment presence. These findings might reflect altered metabolism, and would be associated with harmful clinical effects in terminally ill patients.
Assuntos
Miocárdio/patologia , Desnutrição Proteico-Calórica/patologia , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Lipofuscina/análise , Masculino , Estado Nutricional , Desnutrição Proteico-Calórica/complicaçõesRESUMO
Little is known at present about the saccharide components of lipofuscin (age pigment) and ceroid pigments in situ. The purpose of this study was, therefore, to study in detail the lectin reactivities of lipofuscin in neurons and cardiac myocytes of old humans and rats. In addition, those of diverse ceroid pigments found in human aortic atheromas, in the livers of choline-deficient rats, in the uteri of vitamin E-deficient rats and in the crushed epididymal fat pad of rats, are included. Cryostat and deparaffinized sections from all these tissues were either extracted with a solvent mixture of chloroform-methanol-water (10:10:3, v/v) and incubated with 7 different biotinylated lectins or left untreated. Delipidation was done in order to study whether it was possible to discriminate between the saccharide moieties of glycolipids and glycoproteins of lipofuscin and ceroid pigments in situ. Other similarly treated sections were used to study the autofluorescence, sudanophilia, acid-fastness and reactivity to PAS. The frequency and intensity of lectin binding and standard histochemical properties of all the pigments were evaluated semi-quantitatively and blind. The results indicated that mannose was in general the most consistently detected sugar residue in lipofuscin granules of humans and rats, and that this pigment may also contain acetylglucosamine, acetylgalactosamine, sialic acid, galactose and fucose. However, notable differences were found not only in the lipofuscin saccharide components of different cell types of humans and rats, but also in those in the same type of cells in both species. Although mannose was not detected in the hepatic ceroid of choline-deficient rats, this saccharide moiety was almost always present in the other ceroid pigments. Each of the ceroids also contained other types of saccharides although the frequency of the latter varied between different ceroid pigments. While lipofuscin and each of the ceroid pigments showed somewhat different lectin binding patterns, the variability in the frequency of reactivity to lectins suggests that these patterns may not be permanent but transient. In this sense, it appears that lectin histochemistry may not allow these pigments to be differentiated. Furthermore, the extractive procedures used in this study did not enable us to determine whether the saccharides detected in the pigments in situ corresponded to glycolipids or glycoproteins.
Assuntos
Ceroide/análise , Lectinas , Lipofuscina/análise , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Animais , Química Encefálica , Feminino , Fluorescência , Histocitoquímica , Humanos , Masculino , Miocárdio/química , Miocárdio/citologia , Neurônios/química , Ratos , Ratos Wistar , Coloração e Rotulagem/métodosRESUMO
In an effort to identify the effects of the 3-carbon compound pyruvate on free radical production, we measured hepatic total peroxisomal beta-oxidation and catalase activity and the production of lipofuscin-like products in male Sprague-Dawley rats consuming an adequate diet supplemented with pyruvate, vitamin E, or the peroxisome proliferator and free radical enhancer clofibrate for 22 days (n = 5 in each group). Clofibrate feeding induced hepatomegaly, a fivefold increase in total peroxisomal beta-oxidation activity, and a threefold increase in hepatic lipofuscin-like products (P < .05). Pyruvate but not vitamin E inhibited the increase in liver size by 70% (P < .05). Both pyruvate and vitamin E completely inhibited clofibrate-induced increases in lipofuscin-like products (P < .05). Pyruvate but not clofibrate or vitamin E increased plasma concentrations of the nitric oxide metabolites nitrite and nitrate (P < .05). We conclude that with clofibrate-induced peroxisomal proliferation and free radical production, pyruvate will inhibit peroxisomal proliferation and free radical production, inhibit free radical-induced lipid peroxidation, and enhance metabolism of nitric oxide.